What's he mean by "by 2026?" Is it different from "until 2026?"

Native speaker’s answer
Rebecca
The word "by" means 'no later than', showing that there is a strict deadline. "Until" is used to show how long something will go on for. Ex: I need to finish these Q&As by 5pm or else Eunice will be mad at me! Ex: It's 2pm now. You can finish these Q&As until 5pm, so you have 3 hours.